Question

Find the solution to the system of equations. 4x + 3y = –1 3x – 9y = 33 solution = ( , )

Answer 1

Answer:

(x, y) =(2,-3)

Step-by-step explanation:

4x+3y=-1

3x-9y=33 /:3

4x+3y=-1.....(1)

x-3y=11... (2)

(1)+(2): 5x=10

x-3y=11

x=10/5

x-3y=11

x=2

2-3y=11

x=2

-3y=11-2

x=2

-3y=9

x=2

y=9/(-3)

x=2

y=-3

(x,y)=(2,-3)

Answer 2

Answer:

(2 , -3)

Step-by-step explanation:

4x + 3y = –1

3x – 9y = 33

12x + 9y = –3 (1)

3x – 9y = 33  (2)

We add equation (1) and (2)

12x + 9y = –3

+

3x – 9y = 33

___________

15x + 0 = 30

then x = 30/15 = 2

if we substitute x by 2 in equation (2) we get :

3(2) – 9y = 33 ⇒ 6 - 9y = 33 ⇒ -9y = 33 - 6 = 27⇒ y = 27/-9 = -3

finally, x = 2 and y = -3.

:)